n,m,k = map(int,input().split())
num = min(n,m)*2 - (n==m) 
if k == 0:
  if n != 0 and m != 0:
    print(-1)
    exit()
  else:
    ans = "0"*n + "1"*m
    print(ans)
    exit()
if num < k:
  print(-1)
  exit()
elif num == k:
  if n >= m:
    l = [0,1] *( (k+1)//2 )
  else:
    l = [1,0] * ((k+1)//2)
  if k % 2 == 0:
    l.append(l[0])
else:
  l = [0,1] *( (k+1)//2 )
  if k % 2 == 0:
    l.append(l[0])

cnt = [1]*len(l)
n -= l.count(0)
m -= l.count(1)
for i in range(len(l)):
  if l[i] == 0:
    cnt[i] += n
    break
for i in range(len(l))[::-1]:
  if l[i] == 1:
    cnt[i] += m
    break
  
ans = ""
for i in range(len(l)):
  ans += str(l[i]) * cnt[i]

print(ans)